* {
    margin: 0 auto;
}
body {
    height: 600px;
}
.box {
    margin-top: 30px;
    width: 1200px;
    height: 30px;
    line-height: 30px;
    border: 1px solid green;
    position: relative;
}

.cloud {
    position: absolute;
    background-image:url(../images/云.png);
    background-repeat: no-repeat;
    background-position: -1% 0%;
    background-size: 20% 66%;
    left: 0;
    width: 100px;
    height: 30px;
}

.box ul{
    padding: 0;
}

.box ul li {
    z-index: 9999;
    list-style: none;
    width: 100px;
    float: left;
}

.box>ul>li>a {
    z-index: 9999;
    display: block;
    color: black;
    text-decoration: none;
    text-align: center;
}
